In some wireless networks, a plurality of wireless devices may attempt to access a transmission medium at the same time. The channel access may comprise sensing the channel for pending transmissions. If the transmission medium is sensed to be busy, a wireless device may back off and attempt the channel access after the channel is sensed to be available. Allowing overlapping transmissions may improve spectrum efficiency but induce interference unless managed properly. A node of a first wireless network may allow nodes of a second wireless network to carry out transmissions simultaneously with at least one node of the first wireless network, wherein said node may transmit a control message indicating the allowance of the overlapping transmissions.